TextMate installs a new 'mate' command that can be used to open files and directories from the command line. I don't recall if it installs the command automatically, or if you need to do something special to invoke it, sorry.
Folding can be tricky, as it matches both open/close folding characters for the language you're currently using, and the indent level must be correct as well. Plus, of course, they need to balance correctly.
Not sure about the beeps, I only recall TextMate beeping during a search, if it's found the last occurance and I ask it to find the next one (which there isn't one).
Hope this helps,
- Dave